Process for the continuous dredging of incoherent material, particularly sandy material, with a circular path

ABSTRACT

A process for the continuous dredging of incoherent material, particularly sandy material, with a circular path, including the steps of drawing continuously the incoherent material from a zone where it is brought and conveying, also continuously, said material to an erosion zone, to such an amount as to integrate the same erosion. The drawing is carried out progressively in a zone having the shape of an annular ring, the size of which is such, in relationship with the supply of incoherent material, that at the end of a complete turn of the dredging unit, the initial point will be carried again to its initial level. A device is also disclosed for carrying out the process, comprising a drawing pipe, carried by an arm glidingly mounted on a circular guide, for instance a rail located on a landing stage, hydraulic means for turning said drawing pipe about a horizontal shaft, and a pump suitable to cause the water + sand mud to be drawn by said tube and to be conveyed through trunk line, provided with a knuckle joint coincident with the centre of rotation of the arm and connected to a pipe leading to the delivery zone.

United States Patent [1 1 den Hartog PROCESS FOR THE CONTINUOUS DREDGING 0F INCOIIERENT MATERIAL,

PARTICULARLY SANDY MATERIAL, WITH A CIRCULAR PATH Inventor: Willem Cornelis den liartog,

Kinderdijlt, Netherlands Assignee: N. V. Industrieele l-landellcornbinatle Holland, Kinderijk, Netherlands Filed: Apr. 16, 1911 Appl. No.: 134,654

[52] US. Cl 61/2, 37/58, 37/65 [51] Int. Cl. E02f 1/00, E02d 17/l6 [58] Field of Search 61/2, 3, 35, 7, 1;

[111 3,750,408 [451 Aug. 7, 1973 Primary Examiner-Jacob Shapiro litiar izey l iolman & stem 9 1571 ABSTRACT A process for the continuous dredging of incoherent material, particularly sandy material, with a circular path, including the steps of drawing continuously the incoherent material from a zone where it is brought and conveying, also continuously, said material to an erosion zone, to such an amount as to integrate the same erosion. The drawing is carried out progressively in a zone having the shape of an annular ring, the size of whichis such, in relationship with the supply of incoherent material, that at the end of a complete turn of the dredging unit, the initial point will be carried again to its initial level. A device is also disclosed for carrying out the process, comprising a drawing pipe, carried by an arm glidingly mounted on a circular guide, forinstance a rail located on a landing stage, hydraulic means for turning said drawing pipe about a horizontal shaft, and a pump suitable to cause the water sand mud to be drawn by said tube and to be conveyed through trunk line, provided with a knuckle joint coincident with the centre of rotation of the arm and connected to a pipe leading to the delivery zone.

2 Claims, 5 Drawing Figures IE I AUG 7 ms 5 9 sum 2 OF 5 v PAIENIEU RUB 7 I973 SHEET 5 BF 5 PROCESS FOR THE CONTINUOUS DREDGIING OF INCOIIERENT MATERIAL, PARTKCULARILY SANDY MATERIAL, WITH A CIRCULAR PATH BACKGROUND OF THE INVENTION The present invention relates to a process for the continuous dredging of incoherent material, particularly sand, with a circular path.

It is known that in some zones of the sea-shore the phenomenon of erosion can occur, due to reasons of various and intricate nature, to a more or less intense degree. This phenomenon, in its most intense forms, can originate a remarkable diminution of the sandy shores, with the consequent risk of damages to the buildings located near the same sandy shores.

The purpose of this invention is that of solving in a rational and inexpensive way, the aforesaid problem.

SUMMARY OF THE INVENTION According to this invention, a process is provided consisting in drawing continuously sand from a feed place, and conveying, also'continuously, said sand to the erosion zone, to such an amount as to integrate the erosion itself.

The drawing is carried out progressively in a zone having the shape of an annular ring or channel the dimensions of which are such, in relationship to the sand feed, that at the end of a complete turn of the dredging unit, the initial point will return to its original level.

A device is provided for carry out said process, consisting of a drawing pipe, carried by an arm glidingly mounted on a circular track, for instance a circular rail, located on a landing stage, a hydraulic device for rotating said drawing pipe about a horizontal axis, and a pump capable of causing the water plus sand mud to be sucked by the pipe and to convey it through a trunk line, provided with a rotatable coupling coincident with the centre of rotation 'of the arm and connected to a pipe carrying the material to the zone to be refilled.

BRIEF DESCRIPTION OF THE DRAWINGS This invention will now be described with reference to the attached drawings, showing by way of non limitative example one preferred embodiment of the inventionitself.

In the drawings:

FIG. 1a and lb show a top plan view of the device;

FIGS. 2a and 2b are side elevational views;

FIG. 3 is a diagrammatical top plan view, showing the operating zone of the drawing pipe.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT With reference to FIGS. 1 and 2, the numeral reference 1 denotes the bottom of the sea, and the numeral reference 2 denotes the water level. On the piling 3 is supported the landing stage 4 connecting the plant to the shore. On the piling 3 a plinth-like support 3 is provided with the knuckle point 6 on which is pivoted the rigid box structure 7 consisting of two elements connected at 8. The free end of the structure '7 is mounted on wheels 9 rollong on the circular rail it) having its centre at the joint 6 and supported by the piling ill.

The structure 7 is continued by the arm i2 which can rotate about the hinges i3 due to the action of the hydraulic cylinder 14. As it is shown in FIG. 2, the arm 12 can rotate about a horizontal axis, from its position parallel to the surface of the water, down to its immersed position, as shown in dotted line.The arm 12 is prolonged by the drawing pipe 15 consisting of a set of removable segments 16 and by the terminal angle member 17 provided with a drawing head 18.

The drawing pipe 15 is carried by the fork member 119 which can rotate about the axle 20, due to the action of the hydraulic cylinder 21 one end of which is pivotally connected to the fixed frame 22, while the other end acts in the articulated parallelogram formed by the trestle 23 pivoted at 24, by the rod 25 rigid with the drawing pipe 15 and by the tie rod 26. All movements are controlled by an operator located in the control cabin 27.

The drawing pipe 116 ends in a pump 28 operated by a motor 29. Near to the rotation axle 20, the connection from the drawing pipe to the pump is ensured by a flexible segment 30.

From the delivery side of the pump 28, there is a pipe 31 mounted on the arm 12, on the structure 7 and passing through the knuckle joint 6. Therefrom, the pipe 31 is directed to the non shown supply zone. in register with the axis of rotation 13 there is a second flexible segment 30.

The operation is as follows: with the drawing pipe at its maximum extension (FIG. 2) the drawing element 13 will be caused to rest on the bottom and the pump 28 is operated, drawing thus the water plus sand mud and conveying it through the pipe 31 to the supply zone. Periodically, the entire unit will cause to turn about the centre of rotation 6, through sequential positions. When an entire turn has been effected, the whole unit will be carried on the landing stage d, the last segment to of the drawing pipe will be removed, and the drawing head 18 will be mounted again; repeating then the operative cycle as above described. Of course in alternative way, the dredging operations can also be carried out starting from the minimum extent of the drawing pipe, i.e., with one single element, and adding sequentially the other elements.

FIG. 2 shows the sequential conformations of the drawing pipe, which in the final stage consists of a single segment 16.

A dredging zone will be obtained, as shown in FIGS. 2 and 3, consisting of an annular ring or channel, with a trapezoidal cross sectional shape, defined by the two upper edges A and B, by the bottom C and by the inclined walls D and E, the inclination of which depends upon the friction angle (or angle of slide) of the sandy material.

As aforesaid, the plant is mounted in a zone where the materialis brought, whereby at the end of an entire turn of the unit, the initial part will be substantially carried again to its original level. This fact allows the dredging to carry out continuously for an indefinite time.

The present invention has been described in one preferred embodiment being however understood that changes of execution might be practically adopted without departing from the scope of the present industrial privilege.

Having thus described the present invention, what is claimed is:

ii. A process for continuous dredging of incoherent material from a first to a second operating zone, said first zone containing said material to be dredged, said second zone being eroded of said material, the steps 3 4 comprising: dredging said material in said first zone in 2. A process as claimed in claim 1 wherein the dredgprogresswely mtatmg manner about a complete ing is effected in sequential circular paths having differcular path, which path is in a horizontal plane; and continuously conveying said material from said first zone l to said second zone thereby forming an annular chan- 5 channels 531d first operatlng Zonenel in said first operation zone.

ent radii thereby forming successively larger annular 

1. A process for continuous dredging of incoherent material from a first to a second operating zone, said first zone containing said material to be dredged, said second zone being eroded of said material, the steps comprising: dredging said material iN said first zone in a progressively rotating manner about a complete circular path, which path is in a horizontal plane; and continuously conveying said material from said first zone to said second zone thereby forming an annular channel in said first operation zone.
 2. A process as claimed in claim 1 wherein the dredging is effected in sequential circular paths having different radii thereby forming successively larger annular channels in said first operating zone. 